Rattling
 

The back wheels in my car are rattling everytime i go over a lil bump in the road. At first i thought it was the exhaust hitting something but it isn't. Then I just went back and forth over a bump and i located it to the back wheels. It goes Klanky klank klank (if you can make sense of that). BUt Im just curiuos if anyones has any idea what this is.

Wish I could help... take the wheel out and see?

Um have you tried it with the brakes slightly applied and all the way off?
I had a similar problem and it turned out to be a worn Brake pad that came slightly loose and was rattling. It could be loose Suspension parts like a totally worn bushing causing metal on metal contact, it could be a shot whell bearing but you would hear other sounds liek roaring sounds when driving. the Lugs could be worn causing some weird vibrations but I doubt that because again at speed you would feel it. And your sure it's not the exhaust when the rear is under compression?